I think it may be Isabella Alice Collister (1883) who is one of many children born to David Collister and Mary Moore. Isabella died unmarried on the Island.

There was an Isabella Beatrice Collister born to David James Collister and Elizabeth Shimmin 1860 in Peel.

Isabella Beatrice Collister married John Philip Smart in Liverpool at All Saints ( possibly Toxteth) have you obtained the marriage certificate ?

Len Faragher